Medium
08E on Biasi Advance Plus 16S 25S 30S

Your boiler is struggling to detect the temperature outside, which may cause it to run inefficiently or stop your heating from adjusting correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Faulty external temp. probe NTC

Shared across the Advance Plus range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

01EView →02EView →03EView →

All 23 fault codes on the Advance Plus 16S 25S 30S

Seeing a different code? Every code this model can display, in one place.

01E02E03E04E05E06E09E10E11E14EErEr / RESETEr 01Er 02Er 03Er 04Er 05Er 06Er 08Er 09Er 10Er 14

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